15. Whether it is credible that the men of the primitive age abstained from sexual intercourse until that date at which it is recorded that they begat children.
Some one, then, will say, Is it to be believed that a man who intended to beget children, and had no intention of continence, abstained from sexual intercourse a hundred years and more, or even, according to the Hebrew version, only a little less, say eighty, seventy, or sixty years; or, if he did not abstain, was unable to beget offspring? This question admits of two solutions. For either puberty was so much later as the whole life was longer, or, which seems to me more likely, it is not the first-born sons that are here mentioned, but those whose names were required to fill up the series until Noah was reached, from whom again we see that the succession is continued to Abraham, and after him down to that point of time until which it was needful to mark by pedigree the course of the most glorious city, which sojourns as a stranger in this world, and seeks the heavenly country. That which is undeniable is that Cain was the first who was born of man and woman. For had he not been the first who was added by birth to the two unborn persons, Adam could not have said what he is recorded to have said, "I have gotten a man by the Lord."175 He was followed by Abel, whom the elder brother slew, and who was the first to show, by a kind of foreshadowing of the sojourning city of God, what iniquitous persecutions that city would suffer at the hands of wicked and, as it were, earth-born men, who love their earthly origin, and delight in the earthly happiness of the earthly city. But how old Adam was when he begat these sons does not appear. After this the generations diverge, the one branch deriving from Cain, the other from him whom Adam begot in the room of Abel slain by his brother, and whom he called Seth, saying, as it is written, "For God hath raised me up another seed for Abel whom Cain slew."176 These two series of generations accordingly, the one of Cain, the other of Seth, represent the two cities in their distinctive ranks, the one the heavenly city, which sojourns on earth, the other the earthly, which gapes after earthly joys, and grovels in them as if they were the only joys. But though eight generations, including Adam, are registered before the flood, no man of Cain's line has his age recorded at which the son who succeeded him was begotten. For the Spirit of God refused to mark the times before the flood in the generations of the earthly city, but preferred to do so in the heavenly line, as if it were more worthy of being remembered. Further, when Seth was born, the age of his father is mentioned; but already he had begotten other sons, and who will presume to say that Cain and Abel were the only ones previously begotten? For it does not follow that they alone had been begotten of Adam, because they alone were named in order to continue the series of generations which it was desirable to mention. For though the names of all the rest are buried in silence, yet it is said that Adam begot sons and daughters; and who that cares to be free from the charge of temerity will dare to say how many his offspring numbered? It was possible enough that Adam was divinely prompted to say, after Seth was born, "For God hath raised up to me another seed for Abel," because that son was to be capable of representing Abel's holiness, not because he was born first after him in point of time. Then because it is written, "And Seth lived 205 years," or, according to the Hebrew reading, "105 years, and begat Enos,"177 who but a rash man could affirm that this was his first-born? Will any man do so to excite our wonder, and cause us to inquire how for so many years he remained free from sexual intercourse, though without any purpose of continuing so, or how, if he did not abstain, he yet had no children? Will any man do so when it is written of him, "And he begat sons and daughters, and all the days of Seth were 912 years, and he died?"178 And similarly regarding those whose years are afterwards mentioned, it is not disguised that they begat sons and daughters.
Consequently it does not at all appear whether he who is named as the son was himself the first begotten. Nay, since it is incredible that those fathers were either so long in attaining puberty, or could not get wives, or could not impregnate them, it is also incredible that those sons were their first-born. But as the writer of the sacred history designed to descend by well-marked intervals through a series of generations to the birth and life of Noah, in whose time the flood occurred, he mentioned not those sons who were first begotten, but those by whom the succession was handed down.
Let me make this clearer by here inserting an example, in regard to which no one can have any doubt that what I am asserting is true. The evangelist Matthew, where he designs to commit to our memories the generation of the Lord's flesh by a series of parents, beginning from Abraham and intending to reach David, says, "Abraham begat Isaac;"179 why did he not say Ishmael, whom he first begat? Then "Isaac begat Jacob;" why did he not say Esau, who was the first-born? Simply because these sons would not have helped him to reach David. Then follows, "And Jacob begat Judah and his brethren: " was Judah the first begotten? "Judah," he says, "begat Pharez and Zara;" yet neither were these twins the first-born of Judah, but before them he had begotten three other sons. And so in the order of the generations he retained those by whom he might reach David, so as to proceed onwards to the end he had in view. And from this we may understand that the antediluvians who are mentioned were not the first-born, but those through whom the order of the succeeding generations might be carried on to the patriarch Noah. We need not, therefore, weary ourselves with discussing the needless and obscure question as to their lateness of reaching puberty.
As, therefore, the human race, subsequently to the first marriage of the man who was made of dust, and his wife who was made out of his side, required the union of males and females in order that it might multiply, and as there were no human beings except those who had been born of these two, men took their sisters for wives, – an act which was as certainly dictated by necessity in these ancient days as afterwards it was condemned by the prohibitions of religion. For it is very reasonable and just that men, among whom concord is honourable and useful, should be bound together by various relationships; and that one man should not himself sustain many relationships, but that the various relationships should be distributed among several, and should thus serve to bind together the greatest number in the same social interests. "Father" and "father-in-law" are the names of two relationships. When, therefore, a man has one person for his father, another for his father-in-law, friendship extends itself to a larger number. But Adam in his single person was obliged to hold both relations to his sons and daughters, for brothers and sisters were united in marriage. So too Eve his wife was both mother and mother-in-law to her children of both sexes; while, had there been two women, one the mother, the other the mother-in-law, the family affection would have had a wider field. Then the sister herself by becoming a wife sustained in her single person two relationships, which, had they been distributed among individuals, one being sister, and another being wife, the family tie would have embraced a greater number of persons. But there was then no material for effecting this, since there were no human beings but the brothers and sisters born of those two first parents. Therefore, when an abundant population made it possible, men ought to choose for wives women who were not already their sisters; for not only would there then be no